1. Technical Field
Aspects and embodiments disclosed herein relate to air conditioning systems for cooling buildings such as residential units, and to methods and systems for powering the condensers of such air conditioning systems.
2. Discussion of Related Art
Air cooling systems for buildings, for example, residential units, may be provided as smaller window mounted units, often having the capacity to cool only a single room or a small residence, or as larger whole building units to provide cool air to what is commonly referred to as a “central air” system for cooling multiple rooms of a building or an entire building. Some building cooling systems, for example, “swamp cooler” systems, which are most commonly used in arid areas, have few moving internal components other than a fan to draw air through a moistened mat of material. More common building cooling systems typically rely on the compression and expansion of a refrigerant with a compressor to alternatively heat and cool the refrigerant and provide a heat sink to cool air within a building. These types of cooling systems are usually associated with the term “air conditioner.” A refrigeration cycle in a typical air conditioner uses a motor to drive the operation of a compressor. The compressor causes a pressure change in a refrigerant circulated between two compartments. The refrigerant is pumped through an expansion valve into an evaporator coil, located in a first compartment, where a low pressure environment within the evaporator coil causes the refrigerant to evaporate into a vapor and drop in temperature. A fan circulates air from within the building to be cooled over the evaporator coil to transfer heat from the air into the evaporated refrigerant, cooling the air, which is then directed back into the building. The refrigerant is then directed into a condenser located outside of the cooled compartment, where the refrigerant vapor is compressed and forced through a heat exchange coil, condensing the refrigerant into a liquid and increasing its temperature. An additional source of air is circulated over the heat exchange coil to remove heat from the compressed coolant and deliver it into an environment outside of the building. The refrigerant then passes back through the expansion valve into the evaporator coil where it absorbs additional heat from air in the building. Heat absorbed from the air inside the building is thus transferred outside of the building.
Residential sized air conditioning systems typically rely on electric motors to drive the compressor and circulate the refrigerant through the air conditioning system. At least one larger air conditioning system, the York Triathlon™ Natural Gas Heating and Cooling System (Johnson Controls, Inc., discontinued) included a compressor powered by an internal combustion engine.